33M with right foot drop and numbness after major weight loss — suspected peroneal nerve compression

Hi,

I’m a 33-year-old male, 192 cm tall and currently around 89 kg. I intentionally lost approximately 25–30 kg over the past year.

During a recent occupational medical examination, the doctor noticed that I could not properly stand on my right heel. I was then assessed in a neurological emergency department.

My main symptoms are:

• weakness when lifting the front of my right foot and toes
• difficulty standing or walking on my right heel
• numbness over the outer lower leg, top of the foot, big toe and the space between the first and second toes
• no significant back pain
• no bowel or bladder problems
• no weakness in the face, arms or left leg

The neurological examination showed approximately 3/5 strength in dorsiflexion and foot eversion, while most other muscle groups were normal. Reflexes were symmetrical, Babinski was negative and there were no signs suggesting a central neurological problem.

The doctors suspect a peripheral common peroneal nerve palsy at the fibular head. They mentioned that the large weight loss may have reduced the protective fat around the nerve. I also frequently sit with my legs crossed, sometimes for long periods.

My blood tests were normal. I have now been referred for ENG/EMG nerve-conduction testing, physiotherapy and a peroneal/AFO brace.

My questions are:

• Can frequent leg crossing really cause this degree of peroneal nerve compression and foot drop?
• Does the distribution of numbness and weakness fit compression at the fibular head?
• Should an MRI of the knee, fibular head or lumbar spine also be considered, or is ENG/EMG usually the best first step?
• How likely is recovery when the suspected cause is weight loss and external pressure?
• Is there anything important I should avoid while waiting for further testing?

Thank you very much for any advice.